x_man asks: "This may sound a little strange but I've accumulated a lot of cool stuff throughout my life. Add to that my parent's stuff, my wife's stuff, and all of the other cool stuff I plan to accumulate before I die, and you have a lot of stuff. The problem is what to do with all of this stuff when I die. My descendants will want a few bits, but I can't bear the thought of my 1000+ collection of sci-fi books being scattered to the Goodwill winds. Therefore, I've decided to entomb my stuff. It will all go into an airtight stainless steel shipping container and be buried on a family plot for a 1000 years or so. I will have the ultimate geek time capsule, but there is one problem. Let's say you want to broadcast some sort of locator beacon in a 1000 years. How do you construct a reliable power supply that will last at least 1000 years or more? There's also the question of how to signal future generations. I'm thinking some sort of VLF for ground penetration."